Mayor of London Boris Johnson has advised Southbank Centre that he supports their Festival Wing plans to redevelop the Queen Elizabeth Hall and Hayward Gallery - but not at the expense of the undercroft used by skateboarders.
Southbank Centre revealed its plans to create the 'Festival Wing' in March last year but soon found itself at the centre of a controversy about the future of the undercroft space used for decades by skateboarders and others.
"I wholeheartedly support the principle of enhancing the world-class cultural facilities at the Southbank Centre and am encouraged by many of the aspects of their plans," said Boris Johnson on Wednesday.
"However, redevelopment should not be at the detriment of the skate park which should be retained in its current position.
"The skate park is the epicentre of UK skateboarding and is part of the cultural fabric of London.
"This much-loved community space has been used by thousands of young people over the years.
"It attracts tourists from across the world and undoubtedly adds to the vibrancy of the area – it helps to make London the great city it is."
Southbank Centre had argued that it needed to create new shops and restaurants in the undercroft of the Queen Elizabeth Hall to generate income to service the loans it will have to take out in order to fund the redevelopment.
It had offered to create a new space for skateboarding and street art underneath Hungerford Bridge.
A Southbank Centre spokeswoman said: "We are surprised by the Mayor's unexpected statement.
"We look forward to hearing how he intends to fill the financial gap that now stands between us and our ability to provide free art and culture to millions of Londoners.
"In the meantime the Southbank Centre board must consider the implications for the future of the project if he fails to do so."
Earlier this month members of the Long Live South Bank campaign delivered boxes of objections to Southbank Centre's plans to Lambeth Town Hall.
Southbank Centre artistic director Jude Kelly told BBC London 94.9 on 2 January: "We want Southbank Centre to be part of skateboarding forever."
She added: "We think that if the skateboarders stay exactly where they are and we couldn't use any of that space and we couldn't refurbish, that would be a real loss to millions of people.
"Whereas if we can move the skateboarders 120 metres to a space they really can use forever, then I think that keeps the history going."